Counterfeiting impacts virtually all products and transactions worldwide, with concomitant dwindling public trust in product and transaction authenticity. Average consumers typically find it difficult to distinguish between authentic and counterfeit products, because their outside appearances look the same. It has been estimated that 5 to 7% of all world trade involves counterfeiting, and such illicit trade not only costs global economies many billions in currency each year, but also threatens the lives, health and safety of consumers.
Early anti-counterfeiting techniques typically relied on tags or labels that were affixed to products. For example, one- and two-dimensional bar code symbols were printed on such labels, and were read by specialized electro-optical readers for product identification. Radio frequency identification (RFID) tags were affixed to the products, and were interrogated by specialized RFID readers. Magnetic stripes and holograms were affixed to credit, debit and identification cards, and were also read by specialized card readers. Most of these identification techniques, however, were easily duplicated and defeated by counterfeiters. For example, printed bar code symbols and RFID tags can be easily duplicated or copied. Holograms can be reverse-engineered. Magnetic stripe data can be easily read and reused. These identification technologies are generic, and any generic technology can be copied, duplicated or reverse-engineered, thereby compromising their anti-counterfeiting function.
Subsequent anti-counterfeiting techniques typically employ physically unclonable functions (PUF) that exploit the physical properties of disordered structures, i.e., microstructures characterized by an explicitly-introduced randomness or an intrinsic randomness. PUFs use a challenge-response mechanism. When a physical stimulus is applied to the microstructure (called a challenge), the stimulus interacts with the microstructure of the object and provides a response. Since the microstructure depends on the physical factors introduced in manufacturing and is unpredictable, each challenge-response behavior is different and unpredictable, and this property is used by specialized readers in authentication.
Other anti-counterfeiting techniques include biometrics, such as fingerprints or iris scans, color-shifting inks, magnetic inks, molecular markers using microtaggants, tagging powder, DNA markers, or molecular finger prints, etc. Although generally satisfactory for their intended purpose, the known anti-counterfeiting techniques require specialized proprietary readers that work in laboratory settings. Such readers are unavailable to typical users who wish to authenticate an object in the field, e.g., a consumer who wishes to authenticate a retail product before purchase. Even so, reading an attribute of an object to be authenticated with a specialized reader, converting the read attribute to a code, comparing the code to all of a multitude of codes stored in a database, and indicating when a match between codes has been obtained, all takes considerable time, effort and skill, and, in many cases, so much time, effort and skill that a typical consumer does not wish to bother with performing such authentication.
Accordingly, there is a need for a method of, and a system and label for, authenticating objects that can be quickly and reliably performed in the field by an average user without any special skill set, and without resort to specialized readers, and which authentication cannot be readily copied, duplicated or reverse-engineered.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The system, label and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.